High-strength, high-hardness binders and drilling tools formed using the same

ABSTRACT

Implementations of the present invention include a binder with high hardness and tensile strength that allows for the creation of drilling tools with increased wear resistance. In particular, one or more implementations include a binder having about 5 to about 50 weight % of nickel, about 35 to about 60 weight % of zinc, and about 0.5 to about 35 weight % of tin. Implementations of the present invention also include drilling tools, such as reamers and drill bits, formed from such binders.

CROSS-REFERENCE TO RELATED APPLICATIONS

N/A.

BACKGROUND OF THE INVENTION

1. The Field of the Invention

The present invention generally relates to a high-strength bindermaterial for forming drilling tools and other tools that may be used todrill subterranean formations.

2. Discussion of the Relevant Art

Drill bits and other earth-boring tools are often used to drill holes inrock and other hard formations for exploration or other purposes. Thebody of these tools is commonly formed of a matrix that contains apowdered hard particulate material, such as tungsten carbide. Thismaterial is typically infiltrated with a binder, such as a copper alloy,to bind the hard particulate material together into a solid form.Finally, the cutting portion of these tools typically includes anabrasive cutting media, such as for example, natural or syntheticdiamonds.

To form the body, the powdered hard particulate material is placed in amold of suitable shape. The binder is typically placed on top of thepowdered hard particulate material. The binder and the powdered hardparticulate material are then heated in a furnace to a flow orinfiltration temperature of the binder so that the binder alloy can bondto the grains of powdered hard particulate material. Infiltration canoccur when the molten binder alloy flows through the spaces between thepowdered hard particulate material grains by means of capillary action.When cooled, the powdered hard particulate material matrix and thebinder form a hard, durable, strong body. Typically, natural orsynthetic diamonds are inserted into the mold prior to heating thematrix/binder mixture, while PDC inserts can be brazed to the finishedbody.

The compositions of the matrix and binder are often selected to optimizea number of different properties of the finished body. These propertiescan include transverse rupture strength (TRS), toughness, tensilestrength, and hardness. One important property of the binder is thebinder's infiltration temperature, or the temperature at which moltenbinder will flow in and around the powdered hard particulate material.The chemical stability of the diamonds is inversely related to theduration of heating of the diamonds and the temperature to which thediamonds are heated as the body is formed. Thus, when forming diamonddrilling tools, it is desirable to use a binder with a low enoughinfiltration temperature to avoid diamond degradation.

Binder alloys with low infiltration temperatures are known in the art;however, such binders often sacrifice one or more of tensile strength,hardness, and other desirable properties at the expense of a lowerinfiltration temperature. For example, many conventional copper-tinalloys have a low infiltration temperature, but also have relatively lowtensile strength. On the other hand, many conventionalcopper-zinc-nickel alloys have a low infiltration temperature with arelatively high tensile strength, but also have a relatively lowhardness.

In some cases, drilling tools may be expensive and their replacement maybe time consuming, costly, as well as dangerous. For example, thereplacement of a drill bit requires removing (or tripping out) theentire drill string from a hole that has been drilled (the borehole).Each section of the drill rod must be sequentially removed from theborehole. Once the drill bit is replaced, the entire drill string mustbe assembled section by section, and then tripped back into theborehole. Depending on the depth of the hole and the characteristics ofthe materials being drilled, this process may need to be repeatedmultiple times for a single borehole. Thus, one will appreciate that themore times a drill bit or other drilling tool needs to be replaced, thegreater the time and cost required to perform a drilling operation.

Accordingly, there are a number of disadvantages in conventionaldrilling tools that can be addressed.

BRIEF SUMMARY OF THE INVENTION

Implementations of the present invention overcome one or more problemsin the art with binders with a low-infiltration temperature withoutsacrificing other desirable physical properties. For instance, one ormore implementations include a nickel-zinc-tin ternary alloy binder witha low infiltration-temperature and relatively high tensile strength andrelatively high hardness. One or more addition implementations include acopper-nickel-zinc-tin quaternary alloy binder with a lowinfiltration-temperature and relatively high tensile strength andrelatively high hardness. Implementations of the present invention alsoinclude drilling tools including such binders.

For example, an implementation of high hardness binder for infiltratinga hard particulate material to form a drilling tool. The binder includesabout 5 to about 50 weight % of nickel, about 25 to about 60 weight % ofzinc, and about 0.5 to about 35 weight % of tin. The binder has aliquidus temperature of less than about 1100 degrees Celsius.Additionally, the binder has a hardness between about 75 on the RockwellHardness B scale (“HRB”) and about 40 on the Rockwell Hardness C scale(“HRC”).

Another implementation of the present invention includes a body of adrilling tool that comprises a hard particulate material infiltratedwith a binder. The binder includes about 5 to about 50 weight % ofnickel, about 25 to about 60 weight % of zinc, and about 0.5 to about 35weight % of tin.

In addition to the foregoing, an implementation of a method of forming adrilling tool with increased wear resistance involves providing a matrixcomprising a hard particulate material. The method also includespositioning a binder proximate the matrix. The binder includes about 5to about 50 weight % of nickel, about 25 to about 60 weight % of zinc,and about 0.5 to about 35 weight % of tin. The method further involvesinfiltrating the matrix with the binder by heating the matrix and binderto a temperature of no greater than about 1200 degrees Celsius.

Additional features and advantages of exemplary implementations of theinvention will be set forth in the description which follows, and inpart will be obvious from the description, or may be learned by thepractice of such exemplary implementations. The features and advantagesof such implementations may be realized and obtained by means of theinstruments and combinations particularly pointed out in the appendedclaims. These and other features will become more fully apparent fromthe following description and appended claims, or may be learned by thepractice of such exemplary implementations as set forth hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to describe the manner in which the above-recited and otheradvantages and features of the invention can be obtained, a moreparticular description of the invention briefly described above will berendered by reference to specific embodiments thereof which areillustrated in the appended drawings. It should be noted that thefigures may not be drawn to scale, and that elements of similarstructure or function are generally represented by like referencenumerals for illustrative purposes throughout the figures. Understandingthat these drawings depict only typical embodiments of the invention andare not therefore to be considered to be limiting of its scope, theinvention will be described and explained with additional specificityand detail through the use of the accompanying drawings in which:

FIG. 1 illustrates a reaming shell including a binder in accordance withone or more implementations of the present invention;

FIG. 2 illustrates a surface-set core drill bit including a binder inaccordance with one or more implementations of the present invention;

FIG. 3 illustrates a thermally-stable-diamond (“TSD”) core drill bitincluding a binder in accordance with one or more implementations of thepresent invention;

FIG. 4 illustrates a polycrystalline diamond (“PCD”) core drill bitincluding a binder in accordance with one or more implementations of thepresent invention;

FIG. 5 illustrates a PCD rotary drill bit including a binder inaccordance with one or more implementations of the present invention;

FIG. 6 illustrates an impregnated core drill bit including a binder inaccordance with one or more implementations of the present invention;

FIG. 7 illustrates a cross-sectional view of a cutting portion of theimpregnated core drill bit of FIG. 6 taken along the line 7-7 of FIG. 6;and

FIG. 8 illustrates a chart of acts and steps in a method of forming adrilling tool using a high-strength, high-hardness binder in accordancewith an implementation of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Implementations of the present invention are directed towards binderswith a low-infiltration temperature without sacrificing other desirablephysical properties. For instance, one or more implementations include anickel-zinc-tin ternary alloy binder with a low infiltration-temperatureand relatively high tensile strength and relatively high hardness. Oneor more addition implementations include a copper-nickel-zinc-tinquaternary alloy binder with a low infiltration-temperature andrelatively high tensile strength and relatively high hardness.Implementations of the present invention also include drilling toolsincluding such binders.

As alluded to earlier, one or more binders of the present invention canhave both a high tensile strength and a high hardness, while stillhaving an infiltration temperature suitable for use with natural andsynthetic diamonds. Additionally, one or more binders of the presentinvention include increased wetting abilities for tungsten carbide orother hard particulate materials. The increased wettability of one ormore binders of the present invention can reducing processing times andcan increase bond strength.

As binders often limit the performance of drilling tools, drilling toolsformed with binders of the present invention can have increased drillingperformance. For example, the increased hardness and/or tensile strengthof one or more binders can provide drilling tools with increased wearresistance. The increased wear resistance of drilling tools formed usingbinders of the present invention can increase the drilling life of suchdrilling tools; thereby, reducing drilling costs.

One or more binders of the present invention include about 5 to about 50weight % of nickel, about 25 to about 60 weight % of zinc, and about 0.5to about 35 weight % of tin. In one or more implementations, the bindercan optionally include about 0 to about 60 weight % of copper. Thus, inone or more implementations the binder can comprise a nickel-zinc-tinternary alloy. In one or more alternative implementations the binder cancomprise a copper-nickel-zinc-tin quaternary alloy. One will appreciatethat the exact weight percentage of each of the above listed componentscan be altered to tailor the characteristics of the final drilling tool.

For example, the weight % of nickel in the binder can be increased, orotherwise modified, to increase the wetting abilities of the binder tothe hard particulate material (e.g., tungsten carbide) and/or diamonds,or otherwise tailor additional properties of the binder. Thus, accordingto one or more implementations the binder can include about 5 weight %of nickel, about 10 weight % of nickel, about 15 weight % of nickel,about 20 weight % of nickel, about 25 weight % of nickel, about 30weight % of nickel, about 35 weight % of nickel, about 40 weight % ofnickel, about 45 weight % of nickel, or about 50 weight % of nickel. Onewill appreciate that binders of one or more implementations can includea weight of nickel in a range between any of the above recitedpercentages. For instance, one or more implementations can includebetween about 15 and about 50 weight % of nickel, between about 5 andabout 30 weight % of nickel, between about 5 and about 20 weight % ofnickel, or between about 10 and about 25 weight % of nickel, etc.

The weight % of zinc in the binder can be increased, or otherwisemodified, to increase the strength and ductility of the binder, orotherwise tailor additional properties of the binder. Thus, according toone or more implementations the binder can include about 25 weight % ofzinc, about 30 weight % of zinc, about 35 weight % of zinc, about 40weight % of zinc, about 45 weight % of zinc, about 50 weight % of zinc,about 55 weight % of zinc, or about 60 weight % of zinc. One willappreciate that binders of one or more implementations can include aweight % of zinc in a range between any of the above recitedpercentages. For instance, one or more implementations can includebetween about 30 and about 60 weight % of zinc, between about 35 andabout 50 weight % of zinc, between about 30 and about 40 weight % ofzinc, or between about 35 and about 45 weight % of zinc, etc.

The weight % of tin in the binder can be increased, or otherwisemodified, to increase the hardness, lower the liquidus temperature,increase the wettability of the binder, or otherwise tailor additionalproperties of the binder. Thus, according to one or more implementationsthe binder can include about 0.5 weight % of tin, about 1 weight % oftin, about 2 weight % of tin, about 3 weight % of tin, about 4 weight %of tin, about 5 weight % of tin, about 10 weight % of tin, about 15weight % of tin, about 20 weight % of tin, about 25 weight % of tin,about 30 weight % of tin, or about 35 weight % of tin. One willappreciate that binders of one or more implementations can include aweight of tin in a range between any of the above recited percentages.For instance, one or more implementations can include between about 0.5and about 20 weight % of tin, between about 1 and about 10 weight % oftin, between about 4 and about 15 weight % of tin, or between about 5and about 10 weight % of tin, etc.

As previously mentioned, in one or more implementations the binder canoptionally include about 0 to about 60 weight % of copper. The weight %of copper in the binder can be increased, or otherwise modified, todecrease the liquidus temperature of the binder, or otherwise tailoradditional properties of the binder. Thus, according to one or moreimplementations the binder can include about 10 weight % of copper,about 10 weight % of copper, about 15 weight % of copper, about 20weight % of copper, about 25 weight % of copper, about 30 weight % ofcopper, about 35 weight % of copper, about 40 weight % of copper, about45 weight % of copper, about 50 weight % of copper, or about 55 weight %of copper. One will appreciate that binders of one or moreimplementations can include a weight % of copper in a range between anyof the above recited percentages. For instance, one or moreimplementations can include between about 15 and about 50 weight % ofcopper, between about 5 and about 30 weight % of copper, between about 5and about 20 weight % of copper, or between about 10 and about 25 weight% of copper, etc. In alternative implementations, the binder may notinclude copper.

In one or more implementations of the present invention, the binder caninclude additional components other than nickel, zinc, tin, andoptionally copper. Such additional components can include additionalalloying components, impurities, or tramp elements. In one or moreimplementations such additional components can comprise about 0 to about20 weight % of the binder. In further implementations, such additionalcomponents can comprise less than about 15 weight % of the binder, lessthan about 10 weight % of the binder, or less than about 5 weight % ofthe binder.

In one or more implementation, the additional component(s) can include athermally conductive metal to lower the liquidus temperature of thebinder. Such thermally conductive metals can include, for example,silver, gold, or gallium (or mixtures thereof). For example, accordingto some implementations of the present invention, the binder can includebetween about 0.5 to about 15 weight % silver, gold, or gallium. Onewill appreciate that the inclusion of silver, gold, or gallium cansignificantly raise the cost of the binder.

Alternatively, or additionally, in one or more implementations theadditional component(s) can include further alloying components such asiron, manganese, silicon, boron, or other elements or metals.Additionally, the binder can include minor amounts of various impuritiesor tramp elements, at least some of which may necessarily be present dueto manufacturing and handling processes. Such impurities can include,for example, aluminum, lead, silicon, and phosphorous.

In any event, the composition of the various components can be tailor toprovide the binder with desirable properties. For example, in one ormore implementations the binder has a liquidus temperature of less thanabout 1100 degrees Celsius. Alternatively, the binder has a liquidustemperature of less than about 1050 degrees Celsius. In furtherimplementations, the binder has a liquidus temperature of less thanabout 1000 degrees Celsius. In further implementations, the binder has aliquidus temperature of less than about 950 degrees Celsius. Thus, onewill appreciate that the binder can include a liquidus temperature lowenough to ensure that the infiltration temperature of the binder is lowenough to avoid diamond degradation.

As previously alluded to, binders of one or more implementations of thepresent invention can have high tensile strength and hardness whilemaintaining a liquidus temperature that will avoid diamond degradation.In particular, in one or more implementations the binder has a hardnessbetween about 75 HRB and about 40 HRC. In further implementations thebinder can have a hardness between about 75 HRB and about 20 HRC. Instill further implementations the binder can have a hardness betweenabout 80 HRB and about 95 HRB. One will appreciate that binders of oneor more implementations can include a hardness in a range between any ofthe above recited numbers.

Additionally, binders of one or more implementations can also have atensile strength between about 35 ksi and about 80 ksi, in addition to aliquidus temperatures and hardness as mentioned above. In furtherimplementations the binder can have a tensile strength between about 50ksi and about 70 ksi. In still further implementations the binder canhave a tensile strength of between about 55 ksi and about 65 ksi. Onewill appreciate that binders of one or more implementations can includea tensile strength in a range between any of the above recited numbers.

One will appreciate that binders of one or more implementations of thepresent invention that have high tensile strength and hardness whilemaintaining a liquidus temperature that will avoid diamond degradationcan provide significant benefits. In particular, the high tensilestrength and hardness can provide a drilling tool formed with such abinder with increased wear resistance. The increase in wear resistancecan significantly improve the life of such drilling tools. In addition,the improved wetting can reduce manufacturing time and provide astronger bond.

Thus, the binders of the present invention can be tailored to providethe drilling tools of the present invention with several differentcharacteristic that can increase the useful life and/or the drillingefficient of the drilling tools. For example, the composition of thebinder can be tailored to vary the tensile strength and hardness, andthus, the wear resistance of the drilling tool. One will thus appreciatethat by modifying the composition of the binder, the wear resistance canbe tailored to the amount needed for the particular end use of thedrilling tool. This increased properties provided by binders of one ormore implementations can also increase the life of a drilling tool,allowing the cutting portion of the tools to wear at a desired pace andimproving the rate at which the tool cuts.

The following example present the results of one exemplary bindercreated in accordance with the principles of the present invention. Thisexample is illustrative of the invention claimed herein and should notbe construed to limit in any way the scope of the invention.

EXAMPLE

A binder was formed with 42.62 weight % of copper, 10 weight % ofnickel, 5 weight % of tin, 42 weight % of zinc, and 0.38 weight % ofsilicon. The binder had a tensile strength of 58.5 ksi, a hardness ofHRB 90, and a liquidus temperature of about 926 degrees Celsius. Thus,the binder had both high tensile strength and hardness, whilemaintaining a liquidus temperature below 950 degrees Celsius. The binderwas used to create a reamer with improved properties.

Infiltrated drilling tools of the present invention can be formed from aplurality of abrasive cutting media, a matrix material, and a binder asdescribed above. The binder can be configured to tailor the propertiesof the drilling tools. The drilling tools described herein can be usedto cut stone, subterranean mineral formations, ceramics, asphalt,concrete, and other hard materials. These drilling tools may include,for example, core sampling drill bits, drag-type drill bits, roller conedrill bits, diamond wire, grinding cups, diamond blades, tuck pointers,crack chasers, reamers, stabilizers, and the like. For example, thedrilling tools may be any type of earth-boring drill bit (i.e., coresampling drill bit, drag drill bit, roller cone bit, navi-drill, fullhole drill, hole saw, hole opener, etc.), and so forth. The Figures andcorresponding text included hereafter illustrate examples of somedrilling tools including bodies infiltrated with binders of the presentinvention. This has been done for ease of description. One willappreciate in light of the disclosure herein; however, that the systems,methods, and apparatus of the present invention can be used with otherdrilling tools, such as those mentioned hereinabove.

Referring now to the Figures, FIG. 1 illustrates a first drilling tool100 which can be formed using a binder of one or more implementations ofthe present invention. In particular, FIG. 1 illustrates a reaming shell100. The reaming shell 100 can include one or more bodies 102 (i.e.,pads) formed from a hard particulate material infiltrated with a binderof one or more implementations of the present invention.

The reaming shell 100 can also include a first or shank portion 104 witha first end 108 that is configured to connect the reaming shell to acomponent of a drill string. By way of example and not limitation, theshank portion 108 may be formed from steel, another iron-based alloy, orany other material that exhibits acceptable physical properties.

As shown in FIG. 1, the reaming shell 100 a generally annular shapedefined by an inner surface 110 and an outer surface 112. Thus, thereaming shell 100 can define an interior space about its central axisfor receiving a core sample. Accordingly, pieces of the material beingdrilled can pass through the interior space of the reaming shell 100 andup through an attached drill string. The reaming shell 100 may be anysize, and therefore, may be used to collect core samples of any size.While the reaming shell 100 may have any diameter and may be used toremove and collect core samples with any desired diameter, the diameterof the reaming shell 100 can range in some implementations from about 1inch to about 12 inches.

As shown by FIG. 1, in one or more implementations, the reaming shell100 can include raised pads 102 separated by channels. In one or moreimplementations the pads 102 can have a spiral configuration. In otherwords, the pads 102 can extend axially along the shank 104 and radiallyaround the shank 104. The spiral configuration of the pads 102 canprovide increased contact with the borehole, increased stability, andreduced vibrations. In alternative implementations, the pads 102 canhave a linear instead of a spiral configuration. In suchimplementations, the pads 102 can extend axially along the shank 104.Furthermore, in one or more implementations the pads 102 can include atapered leading edge to aid in moving the reaming shell 100 down theborehole.

In some implementations, the reaming shell 100 may not include pads 102.For example, the reaming shell 100 can include broaches instead of pads.The broaches can include a plurality of strips. The broaches can reducethe contact of the reaming shell 100 on the borehole, thereby decreasingdrag. Furthermore, the broaches can provide for increased water flow,and thus, may be particularly suited for softer formations.

In any event the body or bodies 102 of the reaming shell 100 whetherthey be in the form of pads, broaches, or other configuration can beformed from a matrix of hard particulate material, such as for example,a metal. One will appreciate in light of the disclosure herein, that thehard particular material may include a powered material, such as forexample, a powered metal or alloy, as well as ceramic compounds.According to some implementations of the present invention the hardparticulate material can include tungsten carbide. As used herein, theterm “tungsten carbide” means any material composition that containschemical compounds of tungsten and carbon, such as, for example, WC,W2C, and combinations of WC and W2C. Thus, tungsten carbide includes,for example, cast tungsten carbide, sintered tungsten carbide, andmacrocrystalline tungsten. According to additional or alternativeimplementations of the present invention, the hard particulate materialcan include carbide, tungsten, iron, cobalt, and/or molybdenum andcarbides, borides, alloys thereof, or any other suitable material.

The hard particulate material of the bodies 102 (i.e., pads) can beinfiltrated with a binder as described herein above. The binder canprovide the pads 102 with increased wear resistance. Thereby, increasingthe life of the reaming shell 100.

Optionally, the bodies 102 (i.e., pads) of the reaming shell 100 caninclude also include a plurality of abrasive cutting media dispersedthroughout the hard particulate material. The binder can bond to thehard particulate material and the abrasive cutting media to form thebodies 102. The binder can provide the pads 102 of the reaming shell 100with increased wear resistance, while also not degrading any impregnatedabrasive cutting media.

The abrasive cutting media can include one or more of natural diamonds,synthetic diamonds, polycrystalline diamond or thermally stable diamondproducts, aluminum oxide, silicon carbide, silicon nitride, tungstencarbide, cubic boron nitride, alumina, seeded or unseeded sol-gelalumina, or other suitable materials.

The abrasive cutting media used in the drilling tools of one or moreimplementations of the present invention can have any desiredcharacteristic or combination of characteristics. For instance, theabrasive cutting media can be of any size, shape, grain, quality, grit,concentration, etc. In some embodiments, the abrasive cutting media canbe very small and substantially round in order to leave a smooth finishon the material being cut by the bodies 102. In other implementations,the cutting media can be larger to cut aggressively into the material orformation being drill. The abrasive cutting media can be dispersedhomogeneously or heterogeneously throughout the bodies 102.

One will appreciate that reaming shells 100 are only one type ofdrilling tool with which binders of the present invention may be used.For example, FIGS. 2-4 illustrates four additional types of drillingtools which can be formed using binders of the present invention. Inparticular, FIG. 2 illustrates a surface set drill bit 100 a, FIG. 3illustrates a TSD drill bit 100 b, and FIG. 4 illustrates a PCD drillbit 100 c. Each of the drilling tools of FIGS. 3-5 can include a body102 a, 102 b, 102 c (i.e., bit crowns) comprising a hard particulatematerial, as described above, infiltrated with a binder in accordancewith one or more implementations of the present invention.

Similar to the reaming shell 100, each of the drilling tools 100 a, 100b, 100 c can include a shank portion 104 a, 104 b, 104 c with a firstend 108 a, 108 b, 108 c that is configured to connect the drilling tool100 a, 100 b, 100 c to a component of a drill string. Also, each of thedrilling tools 100 a, 100 b, 100 c can have a generally annular shapedefined by an inner surface 110 a, 100 b, 100 c and an outer surface 112a, 112 b, 112 c. Thus, the drilling tools 100 a, 100 b, 100 c can definean interior space about its central axis for receiving a core sample.

In the case of the surface set drill bit 100 a shown in FIG. 2, theannular crown 102 a can be formed from a hard particulate materialinfiltrated with a binder of one or more implementations as describedabove. Furthermore, the crown 102 a can include a plurality of cuttingmedia 114 a. The cutting media 114 a can comprise one or more of naturaldiamonds, synthetic diamonds, polycrystalline diamond or thermallystable diamond products, aluminum oxide, silicon carbide, siliconnitride, tungsten carbide, cubic boron nitride, alumina, seeded orunseeded sol-gel alumina, or other suitable materials. The binder canbond to the hard particulate material and the abrasive cutting media toform the body 102 a. The binder can provide the crown 102 a withincreased wear resistance, while also not degrading any surface setcutting media.

In the case of the TSD drill bit 100 b and the PCD drill bit 100 c, theannular crowns 102 b, 102 c can be formed from a hard particulatematerial infiltrated with a binder of one or more implementations asdescribed above. Furthermore, the crowns 102 b, 102 c can include aplurality of TSD cutters 114 b or PCD cutters 114 c, respectively. TheTSD cutters 114 b or PCD cutters 114 c can be brazed or soldered to thecrown 102 b, 102 c using a binder of one or more implementations of thepresent invention. Alternatively, the TSD cutters 114 b or PCD cutters114 c can be brazed or soldered to the crown 102 b, 102 c using anotherbinder, braze, or solder.

The drilling tools shown and described in relation to FIGS. 1-4 havebeen coring drilling tools. One will appreciate that the binders of thepresent invention can be used to form other non-coring drilling tools.For example, FIG. 5 illustrates a drag drill bit 100 d including one ormore bodies 102 d formed from a hard particulate material infiltratedwith a binder of the present invention. In particular, FIG. 5illustrates a plurality of blades 102 d from a hard particulate materialinfiltrated with a binder of the present invention. Each of the blades102 d can include one or more PCD cutters 114 d or other cutter brazedor soldered to the blades 102 d. The drag drill bit 100 d can furtherinclude a shank 104 d and a first end 108 d similar to those describedherein above.

One will appreciate the crown 102 c and blades 102 d shown in FIGS. 4and 5 can have an increased drilling life due to the binders of thepresent invention used to form them. This can allow a driller to replacethe cutters 114 c, 114 d multiple times before having to replace thedrill bit 100 c, 100 d.

The binders of the present invention may also be used with impregnatedcutting tools. For example, FIGS. 6 and 7 illustrates views of animpregnated, core-sampling drill bit 100 e having a body or crown 102 eformed with a binder of the present invention. Similar to the othercoring drilling tools 102, 102 a, 102 b, 102 c, the impregnated,core-sampling drill bit 100 e can include a shank portion 104 e with afirst end 108 e that is configured to connect the impregnated,core-sampling drill bit 100 e to a component of a drill string. Also,the impregnated, core-sampling drill bit 100 e can have a generallyannular shape defined by an inner surface 110 e and an outer surface 112e. Thus, the impregnated, core-sampling drill bit 100 e can thus definean interior space about its central axis for receiving a core sample.

The crown 102 of the impregnated, core-sampling drill bit 100 e can beconfigured to cut or drill the desired materials during drillingprocesses. In particular, the crown 102 of the impregnated,core-sampling drill bit 100 e can include a cutting face 118 e. Thecutting face 118 e can include waterways or spaces 120 e which dividethe cutting face 118 e into cutting elements 116 e. The waterways 120 ecan allow a drilling fluid or other lubricants to flow across thecutting face 118 e to help provide cooling during drilling.

The construction of the cutting section of an impregnated drilling toolcan directly relate to its performance. The crown or cutting section ofan impregnated drilling tool typically contains diamonds and/or otherhard materials distributed within a suitable supporting matrix.Metal-matrix composites are commonly used for the supporting matrixmaterial. Metal-matrix materials usually include a hard particulatephase with a ductile metallic phase (i.e., binder). The hard phase oftenconsists of tungsten carbide and other refractory elements or ceramiccompounds.

For example, referring now to FIG. 7, an enlarged cross-sectional viewthe cutting section 116 e of the impregnated, core-sampling drill bit100 e is shown. In one or more implementations, the cutting section 116e of the impregnated, core-sampling drill bit 100 e can be made of oneor more layers. For example, the cutting section 116 e can include twolayers. In particular, the cutting section 116 e can include a matrixlayer 128, which performs the cutting during drilling, and a backinglayer or base 130, which connects the matrix layer 128 to the shankportion 104 e of the impregnated, core-sampling drill bit 100 e.

FIG. 7 further illustrates that the cutting section or crown 116 e ofthe impregnated, core-sampling drill bit 100 e can comprise a matrix 122of hard particulate material and a binder of one or more implementationsof the present invention.

The cutting section or crown 116 e can also include a plurality ofabrasive cutting media 124 dispersed throughout the matrix 122. Theabrasive cutting media 124 can include one or more of natural diamonds,synthetic diamonds, polycrystalline diamond products (i.e., TSD or PCD),aluminum oxide, silicon carbide, silicon nitride, tungsten carbide,cubic boron nitride, alumina, seeded or unseeded sol-gel alumina, orother suitable materials. In one or more implementations, the abrasivecutting media 124 can be very small and substantially round in order toleave a smooth finish on the material being cut by the core samplingimpregnated, core-sampling drill bit 100 e. In alternativeimplementations, the cutting media 124 can be larger to cut aggressivelyinto the material being cut.

The abrasive cutting media 124 can be dispersed homogeneously orheterogeneously throughout the cutting section 116 e. As well, theabrasive cutting media 124 can be aligned in a particular manner so thatthe drilling properties of the cutting media 124 are presented in anadvantageous position with respect to the cutting section 116 e of theimpregnated, core-sampling drill bit 100 e. Similarly, the abrasivecutting media 124 can be contained in the in a variety of densities asdesired for a particular use.

In addition to abrasive cutting media 124, the cutting section 116 e caninclude a plurality of elongated structures 126 dispersed throughout thematrix 122. The addition of elongated structures 126 can be used totailor the properties of the cutting section 116 e of the impregnated,core-sampling drill bit 100 e. For example, elongated structures 126 canbe added to the matrix 122 material to interrupt crack propagation, andthus, increase the tensile strength and decrease the erosion rate of thematrix 122.

Additionally, the addition of elongated structures 126 may also weakenthe structure of the cutting section 116 e by at least partiallypreventing the bonding and consolidation of some of the abrasive cuttingmedia 124 and hard particulate material of the matrix ⁴matrix 122 by thebinder. Thus, when using a binder of the present invention, the additionof elongated structures 126 can help reduce the effective strength ofthe binder to ensure that the crown 102 e will erode and exposeadditional abrasive cutting media 124, while also retaining theincreased wear resistance associated with the increased hardness of thebinder

As shown by FIG. 7, both the elongated structures 126 and the cuttingmedia 124 can be dispersed within the matrix 122 between the cuttingface 118 e and the base 130. As an impregnated drilling tool, the matrix122 can be configured to erode and expose cutting media 124 andelongated structures 126 initially located between the cutting face 118e and the base 130 during drilling. The continual expose of new cuttingmedia 124 can help maintain a sharp cutting face 118 e.

Exposure of new elongated structures 126 can help reduce frictionalheating of the drilling tool. For example, once the elongated structures126 are released from the matrix 122 drilling they can provide coolingeffects to the cutting face 118 e to reduce friction and associatedheat. Thus, the elongated structures 126 can allow for tailoring of thecutting section 116 e to reduce friction and increase the lubrication atthe interface between the cutting portion and the surface being cut,allowing easier drilling. This increased lubrication may also reduce theamount of drilling fluid additives (such as drilling muds, polymers,bentonites, etc.). that are needed, reducing the cost as well as theenvironmental impact that can be associated with using drilling tools.

The elongated structures 126 can be formed from carbon, metal (e.g.,tungsten, tungsten carbide, iron, molybdenum, cobalt, or combinationsthereof), glass, polymeric material (e.g., Kevlar), ceramic materials(e.g., silicon carbide), coated fibers, and/or the like. Furthermore,the elongated structures 126 can optionally be coated with one or moreadditional material(s) before being included in the drilling tool. Suchcoatings can be used for any performance-enhancing purpose. For example,a coating can be used to help retain elongated structures 126 in thedrilling tool. In another example, a coating can be used to increaselubricity near the drilling face of a drilling tool as the coatingerodes away and forms a fine particulate material that acts to reducefriction. In yet another example, a coating can act as an abrasivematerial and thereby be used to aid in the drilling process.

Any known material can be used to coat the elongated structures 126. Forexample, any desired metal, ceramic, polymer, glass, sizing, wettingagent, flux, or other substance could be used to coat the elongatedstructures 126. In one example, carbon elongated structures 126 arecoated with a metal, such as iron, titanium, nickel, copper, molybdenum,lead, tungsten, aluminum, chromium, or combinations thereof. In anotherexample, carbon elongated structures 126 can be coated with a ceramicmaterial, such as SiC, SiO, SiO2, or the like.

Where elongated structures 126 are coated with one or more coatings, thecoating material can cover any portion of the elongated structures 126and can be of any desired thickness. Accordingly, a coating material canbe applied to the elongated structures 126 in any manner known in theart. For example, the coating can be applied to elongated structures 126through spraying, brushing, electroplating, immersion, physical vapordeposition, or chemical vapor deposition.

Additionally, the elongated structures 126 can also be of varyingcombination or types. Examples of the types of elongated structures 126include chopped, milled, braided, woven, grouped, wound, or tows. In oneor more implementations of the present invention, such as when thedrilling tool comprises a core sampling impregnated, core-sampling drillbit 100 e, the elongated structures 126 can contain a mixture of choppedand milled fibers. In alternative implementations, the drilling tool cancontain one type of elongated structure 126. In yet additionalimplementations, however, the drilling tool can contain multiple typesof elongated structures 126. In such instances, where a drilling toolcontains more than one type of elongated structures 126, any combinationof type, quality, size, shape, grade, coating, and/or characteristic ofelongated structures 126 can be used.

The elongated structures 126 can be found in any desired concentrationin the drilling tool. For instance, the cutting section 116 e of adrilling tool 20 can have a very high concentration of elongatedstructures 126, a very low concentration of fibers, or any concentrationin between. In one or more implementations the drilling tool can containelongated structures 126 ranging from about 0.1 to about 25% by weight.In further implementations, the crown 102 e can comprise between about1% and about 15% addition by weight of elongated structures. Inparticular, the crown 102 e can comprise about 3%, 4%, 5%, 6%, 7%, 8%,9% or 10% addition by weight of elongated structures.

According to some implementations of the present invention when thecomposition of the binder is tailored to increase tensile strength, theamount of elongated structures 126 can be adjusted to ensure that thecutting section erodes at a proper and consistent rate. In other words,the cutting portion can be configured to ensure that it erodes andexposes new abrasive cutting media during the drilling process. In thisway, the cutting section 116 e may be custom-engineered to possessoptimal characteristics for drilling specific materials by varying thestrength of the binder and/or concentration of the elongated structures126. For example, a hard, abrasion resistant matrix may be made to drillsoft, abrasive, unconsolidated formations, while a soft ductile matrixmay be made to drill an extremely hard, non-abrasive, consolidatedformation. Thus, the bit matrix hardness may be matched to particularformations, allowing the cutting section 22 to erode at a controlled,desired rate.

In one or more implementations, elongated structures 126 can behomogenously dispersed throughout the cutting section 116 e. In otherimplementations, however, the concentration of elongated structures 126can vary throughout the cutting section 116 e, as desired. The elongatedstructures 126 can be located in the cutting section 116 e of a drillingtool in any desired orientation or alignment. In one or moreimplementations, the elongated structures 126 can run roughly parallelto each other in any desired direction. FIG. 7 illustrates that, inother implementations, the elongated structures 126 can be randomlyconfigured and can thereby be oriented in practically any or multipledirections relative to each other.

The elongated structures 126 can be of any size or combination of sizes,including mixtures of different sizes. For instance, elongatedstructures 126 can be of any length and have any desired diameter. Insome implementations, the elongated structures 126 can be nano-sized. Inother words a diameter of the elongated structures 126 can be betweenabout 1 nanometer and about 100 nanometers. In alternativeimplementations, the elongated structures 126 can be micro-sized. Inother words, diameter of the elongated structures 126 can be betweenabout 1 micrometer and about 100 micrometer. In yet additionalimplementations, the diameter of the elongated structures 126 can bebetween about less than about 1 nanometer or greater than about 100micrometers.

Additionally, the elongated structures 126 can have a length betweenabout 1 nanometer and about 25 millimeters. In any event, the elongatedstructures 126 can have a length to diameter ratio between about 2 to 1and about 500,000 to 1. More particularly, the elongated structures 126can have a length to diameter ratio between about 10 to 1 and about 50to 1.

Implementations of the present invention also include methods of formingimpregnated drill bits including high strength, high hardness binders.The following describes at least one method of forming drilling toolswith binders of the present invention. Of course, as a preliminarymatter, one of ordinary skill in the art will recognize that the methodsexplained in detail herein can be modified. For example, various acts ofthe method described can be omitted or expanded, and the order of thevarious acts of the method described can be altered as desired.

For example, FIG. 8 illustrates a flowchart of one exemplary method forproducing a drilling tool using binders of the present invention. Theacts of FIG. 8 are described below with reference to the components anddiagrams of FIGS. 1 through 7.

As an initial matter, the term “infiltration” or “infiltrating” as usedherein involves melting a binder material and causing the molten binderto penetrate into and fill the spaces or pores of a matrix. Uponcooling, the binder can solidify, binding the particles of the matrixtogether. The term “sintering” as used herein means the removal of atleast a portion of the pores between the particles (which can beaccompanied by shrinkage) combined with coalescence and bonding betweenadjacent particles.

For example, FIG. 8 shows that a method of forming a drilling tool100-100 e can comprise an act 801 of providing or preparing a matrix122. In particular, the method can involve preparing a matrix of hardparticulate material. For example, the method can comprise preparing amatrix of a powered material, such as for example tungsten carbide. Inadditional implementations, the matrix can comprise one or more of thepreviously described hard particulate materials. In some implementationsof the present invention, the method can include placing the matrix in amold.

The mold can be formed from a material that is able to withstand theheat to which the matrix 122 will be subjected to during a heatingprocess. In at least one implementation, the mold may be formed fromcarbon or graphite. The mold can be shaped to form a drill bit havingdesired features. In at least one implementation of the presentinvention, the mold can correspond to a core drill bit.

In addition, the method can optionally comprise an act of dispersing aplurality of abrasive cutting media 124 and/or elongated structures 126throughout at least a portion the matrix. Additionally, the method caninvolve dispersing the abrasive cutting media 124 and/or elongatedstructures 126 randomly or in an unorganized arrangement throughout thematrix 122.

FIG. 8 further illustrates that the method can involve an act 802 ifpositioning a binder proximate the matrix. For example, the method caninvolve placing a binder as described hereinabove on top of the matrix122 once it is positioned in a mold.

In one or more implementations, the hard particulate material cancomprise between about 25% and about 85% by weight of the body 102-102e. More particularly, the hard particulate material can comprise betweenabout 25% and about 85% by weight of the body 102-102 e. For example, abody 102-102 e of one or more implementations of the present inventioncan include between about 25% and 60% by weight of tungsten, betweenabout 0% and about 4% by weight of silicon carbide, and between about 0%and about 4% by weight of tungsten carbide.

The elongated structures can comprise between about 0% and 25% by weightof the body 102-102 e. More particularly, the elongated structures cancomprises between about 1% and about 15% by weight of the body 102-102e. For example, a body 102-102 e of one or more implementations of thepresent invention can include between about 3% and about 6% by weight ofcarbon nanotubes.

The cutting media can comprise between about 0% and about 25% by weightof the body 102-102 e. More particularly, the cutting media can comprisebetween about 5% and 15% by weight of the body 102-102 e. For example, abody 102-102 e of one or more implementations of the present inventioncan include between about 5% and about 12.5% by weight of diamondcrystals.

The method can comprise an act 803 of infiltrating the matrix with thebinder. This can involve heating the binder to a molten state andinfiltrating the matrix with the molten binder. For example, the bindercan be heated to a temperature sufficient to bring the binder to amolten state. At which point the molten binder can infiltrate the matrix122. In one or more implementations, the method can include heating thematrix 122, cutting media 124, elongated structures 122, and the binderto a temperature of at least the liquidus temperature of the binder. Thebinder can cool thereby bonding to the matrix 122, cutting media 124,elongated structures 126, together. The binder can comprise betweenabout 15% and about 55% by weight of the body 102-102 e. Moreparticularly, the binder can comprise between about 20% and about 45% byweight of the body 102-102 e.

According to some implementations of the present invention, the timeand/or temperature of the infiltration process can be increased to allowthe binder to fill-up a greater number and greater amount of the poresof the matrix. This can both reduce the shrinkage during infiltration,and increase the strength of the resulting drilling tool.

Additionally, that the method can comprise an act of securing a shank104 to the matrix 122 (or body 102-102 e). For example, the method caninclude placing a shank 104 in contact with the matrix 122. A backinglayer 130 of additional matrix, binder material, and/or flux may then beadded and placed in contact with the matrix 122 as well as the shank 104to complete initial preparation of a green drill bit. Once the greendrill bit has been formed, it can be placed in a furnace to therebyconsolidate the drill bit. Alternatively, the first and second sectionscan be mated in a secondary process such as by brazing, welding, oradhesive bonding. Still further, additional cutters can be brazed orotherwise attached to the drill bit. Thereafter, the drill bit can befinished through machine processes as desired.

Before, after, or in tandem with the infiltration of the matrix 122, oneor more methods of the present invention can include sintering thematrix 122 to a desired density. As sintering involves densification andremoval of porosity within a structure, the structure being sintered canshrink during the sintering process. A structure can experience linearshrinkage of between 1% and 40% during sintering. As a result, it may bedesirable to consider and account for dimensional shrinkage whendesigning tooling (molds, dies, etc.) or machining features instructures that are less than fully sintered.

Accordingly, the schematics and methods described herein provide anumber of unique products that can be effective for drilling throughboth soft and hard formations. Additionally, such products can have anincreased drilling penetration rate due to the relatively large abrasivecutting media. Furthermore, as the relatively large abrasive cuttingmedia can be dispersed throughout the crown, new relatively largeabrasive cutting media can be continually exposed during the drillinglife of the impregnated drill bit.

The present invention can thus be embodied in other specific formswithout departing from its spirit or essential characteristics. Forexample, the impregnated drill bits of one or more implementations ofthe present invention can include one or more enclosed fluid slots, suchas the enclosed fluid slots described in U.S. patent application No.11/610,680, filed Dec. 14, 2006, entitled “Core Drill Bit with ExtendedCrown Longitudinal dimension,” now U.S. Pat. No. 7,628,228, the contentof which is hereby incorporated herein by reference in its entirety.Still further, the impregnated drill bits of one or more implementationsof the present invention can include one or more tapered waterways, suchas the tapered waterways described in U.S. patent application No.12/638,229, filed Dec. 15, 2009, entitled “Drill Bits WithAxially-Tapered Waterways,” the content of which is hereby incorporatedherein by reference in its entirety. The described embodiments are to beconsidered in all respects only as illustrative and not restrictive. Thescope of the invention is, therefore, indicated by the appended claimsrather than by the foregoing description. All changes that come withinthe meaning and range of equivalency of the claims are to be embracedwithin their scope.

We claim:
 1. A high hardness binder for infiltrating a hard particulatematerial to form a drilling tool, comprising: about 5 to about 50 weight% of nickel; about 25 to about 60 weight % of zinc; and about 0.5 toabout 35 weight % of tin; wherein the binder: has a liquidus temperatureof less than about 1100 degrees Celsius, and a hardness between about 75HRB and about 40 HRC.
 2. The binder as recited in claim 1, a tensilestrength between about 35 ksi and about 80 ksi.
 3. The binder as recitedin claim 1, wherein the binder comprises about 15 to about 50 weight %of nickel.
 4. The body of a drilling tool as recited in claim 3, whereinthe binder consists of: about 15 to about 50 weight % of nickel; about35 to about 60 weight % of zinc; about 0.5 to about 35 weight % of tin;and about 0 to about 20 weight % of additional components.
 5. The bodyof a drilling tool as recited in claim 4, wherein the additionalcomponents comprise one or more of aluminum, iron, lead, manganese,silicon, phosphorous, boron, silver, gold, or gallium.
 6. The body of adrilling tool as recited in claim 3, wherein the binder consistsessentially of nickel, zinc, and tin.
 7. The body of a drilling tool asrecited in claim 1, wherein the binder further comprises about 0 toabout 60 weight % of copper.
 8. The body of a drilling tool as recitedin claim 7, wherein the binder consists of: about 5 to about 50 weight %of nickel; about 35 to about 60 weight % of zinc; about 0.5 to about 35weight % of tin; about 0 to about 60 weight % of copper; and about 0 toabout 20 weight % of additional components.
 9. The body of a drillingtool as recited in claim 7, wherein the binder consists essentially ofnickel, zinc, tin, and copper.
 10. A body of a drilling tool,comprising: a hard particulate material; and a binder, the bindercomprising: about 5 to about 50 weight % of nickel; about 35 to about 60weight % of zinc; and about 0.5 to about 35 weight % of tin.
 11. Thebody of a drilling tool as recited in claim 10, wherein the bindercomprises about 15 to about 50 weight % of nickel.
 12. The body of adrilling tool as recited in claim 11, wherein the binder consists of:about 15 to about 50 weight % of nickel; about 35 to about 60 weight %of zinc; about 0.5 to about 35 weight % of tin; and about 0 to about 20weight % of additional components.
 13. The body of a drilling tool asrecited in claim 12, wherein the additional components comprise one ormore of aluminum, iron, lead, manganese, silicon, phosphorous, boron,silver, gold, or gallium.
 14. The body of a drilling tool as recited inclaim 11, wherein the binder consists essentially of nickel, zinc, andtin.
 15. The body of a drilling tool as recited in claim 10, wherein thebinder further comprises about 0 to about 60 weight % of copper.
 16. Thebody of a drilling tool as recited in claim 15, wherein the binderconsists of: about 5 to about 50 weight % of nickel; about 35 to about60 weight % of zinc; about 0.5 to about 35 weight % of tin; about 0 toabout 60 weight % of copper; and about 0 to about 20 weight % ofadditional components.
 17. The body of a drilling tool as recited inclaim 15, wherein the binder consists essentially of nickel, zinc, tin,and copper.
 18. The body of a drilling tool as recited in claim 1,wherein the drilling tool comprises one of a reamer, a reaming shell, asurface set drill bit, a PCD drill bit, or a diamond impregnated drillbit.
 19. The body of a drilling tool as recited in claim 18, furthercomprising a plurality of abrasive cutting media dispersed throughoutthe body.
 20. The body of a drilling tool as recited in claim 19,wherein the abrasive cutting media comprise one or more of naturaldiamonds, synthetic diamonds, aluminum oxide, silicon carbide, siliconnitride, tungsten carbide, cubic boron nitride, alumina, or seeded orunseeded sol-gel alumina.
 21. A method of forming a drilling tool withincreased wear resistance, comprising: providing a matrix comprising ahard particulate material; positioning a binder proximate the hardparticulate material, the binder comprising about 5 to about 50 weight %of nickel, about 35 to about 60 weight % of zinc, and about 0.5 to about35 weight % of tin; and infiltrating the matrix with the binder byheating the matrix and binder to a temperature of no greater than about1200 degrees Celsius.
 22. The method as recited in claim 21, furthercomprising: dispersing a plurality of abrasive cutting media throughoutthe matrix prior to infiltrating the matrix; wherein the abrasivecutting media comprise one or more of natural diamonds, syntheticdiamonds, aluminum oxide, silicon carbide, silicon nitride, tungstencarbide, cubic boron nitride, alumina, or seeded or unseeded sol-gelalumina.
 23. The method as recited in claim 21, wherein the binderconsists of: about 5 to about 50 weight % of nickel; about 35 to about60 weight % of zinc; about 0.5 to about 35 weight % of tin; about 0 toabout 60 weight % of copper; and about 0 to about 20 weight % ofadditional components.
 24. The method as recited in claim 21, whereinthe binder consists of: about 15 to about 50 weight % of nickel; about35 to about 60 weight % of zinc; about 0.5 to about 35 weight % of tin;and about 0 to about 20 weight % of additional components.
 25. Themethod as recited in claim 23, wherein the additional componentscomprise one or more of aluminum, iron, lead, manganese, silicon,phosphorous, boron, silver, gold, or gallium.